All these slow queries are causing very high MySQL usage (600-700%) which is in turn slowing down the whole server. I have an E3-1240v2 w/ 16GB RAM, so it isn't a slouch. My WooCommerce website gets roughly 10,000 unique hits a day with about 4,000-5,000 downloading something every day (we offer lots of freebies). We are using InnoDB for our tables.

The above mentioned query is what is slowing down my whole server; it is running hundreds of times and I'm not sure why. Apparently it is used when woocommerce_customer_bought_product() is called. When is that function called? Why is it being used so much?